This invention relates to an engine with a turbo-charger for an outboard motor and more particularly to an improved and compact turbo-charged and intercooled internal combustion engine.
It is well known that the power output of an internal combustion engine can be improved through the use of turbo-charging. The turbo-charger compresses the inlet air charge delivered to the engine and hence offers a possibility for increasing its power output. However, the utilization of a compressor for the intake air charge causes a rise in temperature of the intake air charge and this can reduce the actual output generated by the supercharging. It has, therefore, been proposed so as to cool the compressed charge through the use of an intercooler. These concepts are frequently employed with two-cycle internal combustion engines which are particularly advantageous applications for turbo-charging and the use of intercoolers.
However, one of the largest applications for two-cycle internal combustion engines is in connection with the power unit for an outboard motor. Because of the extremely compact nature of an outboard motor, it is desirable to provide a larger than normal power to weight ratio and power to size ratio for such an engine. Thus, there is a particular desirability towards turbo-charging the driving engine of an outboard motor. However, these space limitations of an outboard motor make it very difficult to locate a turbo-charger so as to provide effective and efficient turbo-charging. Furthermore, the very compact space of an outboard motor makes it very difficult to achieve adequate, if any, intercooling.
It is, therefore, a principal object of this invention to provide an improved arrangement for turbo-charging an engine.
It is a further object of this invention to provide an improved, turbo-charged outboard motor.
It is a still further object of this invention to provide an improved arrangement for turbo-charging and intercooling an outboard motor.